spdif / 5.1

Setting up my HT - bought a new sound card for the computer so I could use Dolby 5.1 for video games through the HT system.
The card "soundblaster audigy2" can output a digital 5.1 signal (which sounds to me like it expects the receiver to do the decoding) via an SPDIF connector. This doesn't look like an RCA connector to me. It looks smaller, like a mini headphone jack connector.
Can anyone enlighten me on what cable type / cable ends are needed to get the digital signal from the card to the receiver?